code: def transformer(data, label):
      data = data.reshape((-1,)).astype(np.float32) / 255
      return data, label
  
file_path: mxnet/example/gluon/mnist/mnist.py
imports: from __future__ import print_function
  import argparse
  import logging
  import numpy
  import mxnet
  from mxnet import gluon, autograd
  from mxnet.gluon import nn
label_desc: Use image node_id 1 for calling a global function with example usage: transformer(data, label) and returns: data,  label